Contrivance for fastening woodwork



1,663,580 B. s. ANDERSIN Comvm FOR mswsume woonwonx Filed Dec. 1. 1926 2sneets-sneet1 March 27, 1928.

B. S. ANDERSIN March .27, 1928. 1,663,580

CONTRIVANCE FOR FASTENING WOODWdRK Filed Dec. 1. 1926 2 Sheets-Sheet 2Patented Mar. 27, 1928.

UNITED STATES PATENT OFFICE.

BRUNO SEVERIN ANDEBSIN, OF HELSINKI, FINLAND.

CONTBIVANCE FOR FASTENING WOODWORK.

Application filed December 1, 1928, Serial No. 152,044, and in FinlandNovember 12, 1925.

In the fastening of woodwork, for in stance, in the manufacture ofboxes, where boards are fastened together, the manner of fastening hasvaried considerably, for in- 6 stance, dovetailing with or withoutgluing.

These manners of i'astening have, however,

generally been defective in so far as they do not withstand. dampness orcan not resist forces acting upon the joints or tending to 19 displacethe'boards relatively to one another in the direction of the joints. Theob ect of my invention is to produce a fastening that will, as far aspossible, resist all forces acting upon the joints, and also will with-6 stand the effect of dampness.

How this problem has been solved by the present invention, will be seenclearly from the following, with reference to the accompanying drawing,in which Fig. 1 is a top plan view of one embodiment ofthe new fasteningmeans.

Fig. 2 a section along line 2-2 in Fig. 1,

Fig. 3 a side view. I

In Fig. 41- is seen the fastening side of one of the pieces of wood tobe; fastened to another.

Fig. 5 shows two pieces of wood fastened together by the new fastening.means.

Fig. 5 is a cross-section along line V-V inFig. 5.

Fig. 6 shows a tool required for applying the invention a portion beingbroken off.

Fig. 7 is a top plan View of a modification. Fig. 8 is a side viewthereof. Fig. 9 shows the fastening side of the board.

Fig. 10 again shows the finished fastening. Fig. 11 shows a. toolrequired for fastening, a portion being broken off.

Fig. 12 shows the way of milhng the groove in the boards that are to befastened to one another, while Fig. 13 is a top view of anothermodifieation. a According to Figs. 13 the fastener consists of acorrugated metal. plate, from which have been stamped projecting tongues2, that can be, for instance, placed diagonally opposite one another, asseen in Fig. 1. The

{)0 plate is in this case round, and from its centre a polygonal hole(for instance square) 3, with its projecting edge tongues 4 has beenstamped out.

Now, for the fastening together of two pieces of wood 5 and 6, asemi-circular groove 7 is first of all milled in both which groovecorresponds in size to the diameter of the fastener. For this purpose atool of the kind illustrated in Fig. 6 is used, having a circular bit 8.The part of the shaft 9 that is nearest thebit v8 is provided withmilling teeth 10 like the bit 8. When the groove 7 is out, the teeth onthe shaft 9 also cut a semi-circular opening 11. When the groove 7 hasbeen milled in both pieces, the fastener 1 is fittedinto the grooves,and the edges of the boards are then pressed together. The fastener isnow in such a position in relation to the joint 12, that the projectingtongues 2 assume the position 2" (Fig. 5). Now a suitable key isinserted into the hole 3, and thev fastener thereby is turned, forinstance, in the direction of the arrow 13 (Fig. 5) about an angle ofabout 90, so that the tongues come to the position 2 Thereupon the edgetongues 4 of the hole 3 are pressed, by means of a suitable tool,against the edges of the circular hole 14 formed by theseinicircularopenings 11. The edge tongues 4: can, if desired, be so long, that theycan be bent over the outer surface of the wooden pieces. Thus thefastening is completed. As the fastener 1 is turned, the tongues 2 willbite into the wood, for the groove 7 is namely so shallow, thatthetongues 2 are forced into the wood, as the fastener is turned. Such afastening capable of resisting bending, by reason of the fastener;beingmade of corrugated plate. Also the tongues 2 guaranteeresistance'against tension in the direction of the double arrow 15, aswell as a certain resistance against the displacement of the pieces 5and 6 in the direction of the double arrow 16. The edge tongues 4likewise resist thelatterjdisplacement.

The fastener lshown in Figs.*712 also consists of around corrugatedmetal plate, and there are also diagonally placed tongues 2, but in thisembodiment the tongues are less inv number, for instance onev tonguebeing sufficient for each of the pieces to be joined. For the use ofthis fastener, a groove is milled out from the wooden pieces 5 and 6,shown in Fig. 9. F or this purpose the tool illustrated in Fig. 11 isused. The teeth of the cutter are indicated at 10. With this tool, asemi-circular groove is milled out, equal to the thickness a of thetool, whereupon the tool is pressed down a distance equal to 6, wherebya groove 7 of the desired shape is obtained. The'fastener is then placedbetween the two pieces '5 and 6 in such a manner that the tongues are inthe position 2 (Fig. 10). Then the fastener is turned in eitherdirection tobring the tongues to the position 2 The tongues will not cutinto the wood, but move in the roomier peripheral part of the groove 7.This may bean advantage, when using harder woods.

In the latter form the fastening willbe still better if, during themilling of the groove 7,the tool illustrated in Fig. 11 is pressed intoboth pieces of wood, or only one of them, so deep that'the groove 7becomes somewhat deeper than the semi-circular shape indicates, and iffor instance the curve 17 inFig. 12 equals the semi-circle, the cutterispressed in so far that-the curve 18 gives the boundary of the'milledgroove 7, and only then the roomier peripheral part of the groove 7 ismilled'out. As the fastener is turned, the tongues 2 are pressed againstthe knee formed by the roomier peripheral part of the groove 7 and itsnarrower middle part, whereby a. tight'fastening is obtained.

In the fastener illustrated in Figs. 7 12, such long tongues 2 can beused, if desired, that as the fastener is turned they, will all cut intothe wood, irrespective of the roomier peripheral part of the groove 7.

The fastener need of course not be round, it can be rectangular,-square,a polygon, etc, even though the grooves are milled to asemi-circularshape. Alsoythe-groove 7 in both pieces of wood intended tobe fastened together need not necessarily besemi-cironlar even if aroundfastener be used. In Fig. 13 is shown a fastener that is not round. v

Furthermore, the hole 3 need not neces sarily be in the middle ofthefastener, because if, for instance, one of the pieces of wood to befastened together is very narrow, so that'there is no room" for a. deepgroove 7, or if for some other reason the fastener shall not go equallydeepinto the two pieces of wood. such a fastener can be used, in whichthe hole isnotin the middle but more to one side of the fastener. Thefastener can be made of metal or any other suitable material adaptedforwood fastenings. Instead of the shape'of-the groove 7 shown in Fi'g.9-the groove can beenlarged stepwise towards the circumference, toproduce additional shoulders. In this case, fasteners with additionalpairs of tongues can be used.

The opening at the fastening place can be filled in, if so desired inany suitable manner.

I claim:

1. A fastener for fastening together two pieces of wood comprising asubstantially flat member adapted to be inserted into a groove cut intothe joining faces of the. pieces of wood to be fastened together, andhaving tongues projecting from the plane of said member and adaptedtobite into the wood. upon a turning of said member in en id' groove.

2. A fastener of the type described. com prising a substantially flatmember adapted to be inserted into a groove provided in the parts to bejoined, and having tongues prr=- jecting from the plane of said member,and an angular hole for the insertion therein of a tool to turn saidmember in said groove.

3. A fastener of the type described, comprising a si-ibstan'tially flatmember to be inserted into a grooveprovided parts to be joined, andhaving opposed en tongues projecting from the plane of said member, anCadapted to engage the ma terial of the parts to be fastened together.

A fastener of the type described, comprising a corrugated member adaptedto be inserted into a groove provided in the p ts to be joined andhavingtongues project: g from the plane of said member adapted to cut into thewooden parts to be jo ned upon a turn of said-member.

5. The fastener as specified in claim 4-, comprising a polygonal holehaving edged tongues projectii therefrom at :ulbstantially right anglesto the plane of said member.

6. A fastener for fastening together wooden parts comprising asubstantially l'lat member adapted to be inserted into a groove out intothe joining faces of the wooden parts and having a shoulder, tonguesprojecting from the plane of said member opposite to each other andadapted to bear against the shoulder in said groove upon said memberbeing turned therein.

In testimony whereof I aiiix my signature.

BRUNO SEVERIN AND ER SIN.

